1. Field of the Invention
The invention relates to surface heating, method for its production, and heatable object, and seat occupancy recognition, seat with it, and seat occupancy recognition method, and a heatable object with such a surface heating and a method for the production of a surface heating. More particularly, the invention under consideration relates to a seat heating, a heated seat, and a method for its production. Preferably, the invention also relates to a heating for side linings and floor coverings, particularly in vehicles, side linings and floor coverings equipped with it, particularly in vehicles, and a method for its production. Furthermore, the invention under consideration relates to a mattress heating, a heated mattress, and a method for its production.
2. Prior Art
From actual practice, seat heatings are known, for example, for motor vehicles, which represent, in the sense of the invention, a surface heating and are formed by metal wires with a current through flow, as heating wires, and which are located between upholstery layers. This requires not only an expensive structure of a correspondingly equipped seat, but rather has disadvantages, in particular in operation. Thus, as a result of the stronger heating of surrounding layers in the immediate vicinity of the heating wires, there is a danger of overheating, which can lead to damage to the upholstery layers and/or the heating wires and can even cause a fire. Furthermore, the heat distribution over the surface is not optimal, since in the area of the heating wires, the temperature is always higher than at a distance from it. Another disadvantage with this known mode of construction is the mechanical stress which the heating wires are exposed to, if a passenger uses the seat, since in this way, the conductor wires can break, which can lead to a function failure and/or results in another possible fire source.
From DT 26 16 771 A1, an assembled heating body is known, which provides directed heat radiation and is formed from a plastic laminated plate with the incorporation of a semi conducting layer. This laminated plate consists of a rigid plastic laminated structure, which is formed from at least one layer of a reinforced substrate base material and a resin coat on this material, a semi conducting, carbon-containing prepolymer, which is bound to a heat-resistant, inorganic oxide carrier with a large surface, which is incorporated, as a layer, on at least one side of the layer of the substrate material, a heat-reflecting layer, incorporated in a position on one side of the prepolymer on the substrate material, and current supply devices to parts of the layer made of conductive, carbon-containing prepolymer at a distance from one another, and which produces electrical resistance heating in the laminated plate, which is reflected and radiated off by the heat-reflecting layer of the assembled body. Such heating plates are intended to be used as a part of a wall of a living space or an office.
In this state of the art, the incorporation of the semi conducting layer into the laminated plate can take place in that finely commuted, carbon-containing prepolymer, in the form of small particles or as a powder, is mixed with a suitable carrier or vehicle in such a way that it can be put on, spread, or applied in some other way on the surface of a resin-coated glass cloth, paper, felt, cardboard, and the like, as a laminated substrate or on a wood veneer, which is used in the laminated plate. Instead of that, the finely commuted, carbon-containing prepolymer can also be mixed with the resin or polymer material, with which a special, reinforcing base material is to be impregnated or which is to be applied on this base material as a coating, wherein this base material delivers at least a substrate material layer of the laminated plate. The resulting mixture is applied in or on the substrate by immersion or coating, and the resulting coated substrate is subjected to a semi-curing of the type such that the semi conducting prepolymer conveys a uniform impregnation and coating over the resulting, semi-cured laminated sheet.
DE 33 16 182 A1 deals with the use of molded articles, such as films, plates, or spatially formed structures, from the class of pyrrole polymers, which are complexed with anions, as electrical heating elements, in particular, for the heating of corrosive liquids or gases. The molded articles can thereby also be coated with organic plastics.
A polymeric composite heating element is described in DE 35 24 631 A1 and has the form of a film, tube, or rod. Such polymeric composite heating elements can be used, as such, as heating sources or can be laminated with traditional plastic films, in order to improve the material strength.
The use of electrically conductive, thermoplastic polyurethanes and their production are known from DE 33 21 516 A1. Corresponding products are suitable for, among other things, the production of films having a thickness of 1 to 2 mm for surface heating elements.
Thus, basically heating devices with electrically conductive plastic are known, but the entire state of the art does not have any indications or suggestions as to how such heating devices must be produced and equipped, in order to be able to use them in actual practice.
In a number of other publications of international patent classes H05 B 3/36 and 3/84, surface heatings, which have a layer made of electrically conducting plastics, are explained with examples of outside mirrors for motor vehicles. Essentially, films made of electrically conducting plastics on rigid carriers are thereby used. Use of a film made of electrically conducting plastics on the carrier structure of a motor vehicle seat, however, is not possible, since then all of the upholstery layers etc., lying over it, would be heated, until the heat came to a sitting passenger, which would consume a very large amount of energy.